Sternad, however, is expected to strike a plea deal as he cooperates with federal authorities as part of their investigation into Rivera, a Republican, and the former U.S. representative's close friend, Ana Alliegro, who managed Sternad's disastrous campaign. Sternad ran as a Democrat.

Neither Rivera nor Alliegro is listed by name in the 10-page federal charging document, which lists nameless "co-conspirators."

The co-conspirators helped steer $81,485 in cash to Sternad, who intentionally disguised the illegal campaign contributions by failing to list them on his federal campaign-finance reports.

The money paid for printing and mailing services for a batch of fliers, some of which attacked a Rivera rival, Democrat Joe Garcia, who beat Sternad in the Aug. 14 Democratic primary for the Kendall-to-Key West Congressional District 26 seat. Garcia went on to beat Rivera in the general election.

During the primary, Garcia's campaign complained that Sternad was a ringer, a stand-in attack dog doing Rivera's bidding.

Rivera, who has maintained his innocence, refused comment but pointed to past statements in which he said he never has been informed by authorities of a federal investigation.